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rtoz writes: A MIT spinout company aims to end the landfilling of plastic with a cost-effective system that breaks down nonrecycled plastics into oil, while reusing some of the gas it produces to operate. To convert the plastics into oil, this new system first shreds them. The shreds are then entered into a reactor — which runs at about 400 degrees Celsius — where a catalyst helps degrade the plastics' long carbon chains. This produces a vapor that runs through a condenser, where it's made into oil. Much of the system's innovation is in its continuous operation (video). This company aims to produce more refined fuel that recyclers can immediately pump back into their recycling trucks, without the need for oil refineries. Currently, 2 trillion tons of plastic waste is sitting in U.S. landfills, so there is a huge demand for this technology.

If this technology is so good like they said, and many companies (or better: governments) adopt such ways of transforming plastic into fuel, we can organize all the World plastic waste in to TWO recycle ways: produce FUEL and recycle PLASTIC. We don't need to transform all the plastic waste into fuel. The industry still needs plastic in their products so with a better equilibrium we can reduce the petroleum extraction (a.k.a.: dependency), try to utilize all the annual plastic waste, and (better) we can con

I suspect that it's easier to just make it into oil, even the techically 'recyclable' plastics, due to contamination with dyes and other such things: I suspect making clear or lighter-colored plastics from recycled stuff is hard if not impossible, though dark colors may be easy enough to work with.

On the other hand, it's probably going to be easier(in terms of cost, energy etc) to just make oil out of all of it which goes into reducing fuel consumption, and use that oil for making new plastic.

You have an interesting point. If (and only if) the process of making oil from plastic were (1) LESS EXPENSIVE than recycle used plastic into new plastic for the industry AND (2) the oil produced could be used into the plastic industry in a way it could be at least the same cost in comparison with the petroleum-to-plastic traditional industry way, it will be better to just transform all the world plastic waste into oil, and then redirect its final product to (A) fuel for machines and (B) the plastic industr

More importantly is that only A or B will likely be the best use, not both. Comparative advantage.

Even if the oil production could be enough for both use? I believe that we have a lot of plastic waste worldwide. And if this process could be so good and product a lot in less time, less money etc, maybe we could re-enter this final product in both ways: (A) fuel for machines AND (b) the plastic industry. Or economically speaking, even in this case scenario it will be better following ONLY A or B?

They have been doing this in South American countries for years. Venezuela and Brazil. And its more of a gasoline that comes out and not oil. The Oil companies most likely have been suppressing this info here for years as well.

Do you have some link to share with us about this process made in Brazil and Venezuela? I't would be interesting to learn more about it.

yes, i totally agree but landfill is pollution as well including all the polluting trucks used to transport the plastic to landfill and dig the holes for the rubbish. i guess not a problem for somewhere like the US where they have vast open spaces to create landfill.

If all councils had a small plant in their area to convert the plastics, they could use the oil to run their vehicles and save money until such time all plastics are biodegradable and electric vehicles are the norm.

Why even bother with the landfills? There are massive garbage patches floating around in the oceans, the vast majority of which are plastics. If you can get a big enough tanker and implement this system on it, you could probably cut the amount of fuel needed even further - the tanker goes into a garbage patch, melts all the plastic down, keeps the oil, and uses some of it to get back to land. It would probably be more effective than loading fleets of trucks.

This. With modern simple filtering systems, you should be able to filter even the tiny particles out of the water and turn them into oil.

However, we really need to do both: One set of these devices for breaking down plastic that would otherwise be landfilled(and help pay for garbage collection in the process), and one for ocean recovery.

The problem is that you also end up filtering out all the other life out of the ocean; amoeba, plankton, larvae stages of fish and crustaceans, which sortof defeats the purpose of trying to filter out the plastic in the first place.

That's the hard part - finding something that will remove the plastic but not the DNA lifeforms.

The OP was talking about specific areas of the ocean where plastic accumulates due to currents, not the entire ocean itself.

Further, you start with the big stuff and all those critters would fall through the mesh. You could still have a person or two check what comes up and toss the wiggling stuff back into the water, but the amount of life that would be impacted is essentially zero compared to the amount of life which is currently being affected by these islands of plastic or ingestion of all those micro

We seem fine filtering out the sea life with our fishing nets. The smaller stuff is actually more robust and quicker to regenerate than the bigger fish stocks we are depleting. Atleast in this case we are doing something constructive over all. So what if a little algae and plankton get sucked up too. It's not like they are an endangered species.

There is really not much alive in the atlantic garbage patch, which is where this tech would be best used at sea. (Which, if you've never heard of it, is a place in the Atlantic where a bunch of ocean currents sort of cancel each other out, and makes a place where all sorts of nastiness from all over the world collects, poisoning the area in the process)

Unfortunately, those ocean garbage patches average four 5 X 5 X 1 mm piece of plastic per cubic meter so while a clean up tanker would be great for the environment it wouldn't collect enough to make a meaningful dent in its own fuel needs.

Does such tanker have to be fast and/or work day and night? I could imagine one solar- and wind- powered. A fleet of such tankers might clean up the ocean slowly but steady, providing a constant "stream" of plastic fuel.

So we need to develop an ultrabright nuke that will melt all of the particles into a thin film of plastic that can be collected... or allowed to sink to the bottom dragging all aquatic forms of life with it... oh.... I guess not.

This Wikipedia page [wikipedia.org] has some data. Even at the center of they gyre, there are only a few pieces of confetti sized plastic per square meter. If you were on a boat passing through the patch, you would notice nothing but apparently clean water. There is not nearly enough plastic out there to make collection economically feasible.

Expanding on that, the US Navy (and I'm sure other nation's ship fleets) have excellent nuclear reactors. Even with current technology, thermal depolymerization wouldn't be that hard to do, especially near the Pacific Gyre with the large amount of floating waste available there. Then said ship either stays put, transferring the recovered crude to another vessel, or returns to harbor with useful resources.

A heat source is not the problem here since the stuff is a fuel in itself. I suspect the above poster just wanted to push a nuclear agenda by attaching it to something unrelated, but I could be wrong and they may just be so fixated on a topic that "when you've got a hammer everything is a nail" applies. Maybe we should let "mlts" let us know instead of both of us trying to explain what his mostly unrelated post was about? For all we know it could just be about being able to stay at sea for months at a ti

Though, i think he was saying that due to the nuclear reactor on board the ship, they could stay at sea basically indefinitely (or until their crew runs out of food), and also that the nuclear reactor would provide the heat needed for the plastics conversion.

The garbage patches aren't really big piles of plastic. They're areas above some theshold of plastic to water but still vastly more water than plastic. You'd have to develop something to suck in water and filter out the plastic before you could even start on converting it.

More like a combination between a queen excluder and an inclined plane, so the dolphins would be rejected out an alternate chute. It didn't matter if some oil and/or water went, too, because it would just get sucked back in.

Intake was a suck-start trap siphon, a big round opening that was above sea level at the top but dipped down like a J trap, then came up and over and down. Water was pumped in above the down flow, which had open exit to air, but would be blocked by mass of water: the moving water cr

I think the gold in seawater might be more valuable than the plastic. With gold at 0.000011 ppm in seawater and $42.27 per gram, a cubic meter of seawater contains 1/20 of 1 cent worth of gold. Assuming that the garbage patches have 0.1 ppm plastic and a scrap price of $0.50/pound, a cubic meter of seawater has about 1/100 of 1 cent of plastic.

In other words, if you're going to be doing all that work to mine the seawater, you'll do better off extracting gold from it than plastic!

Why even bother with the landfills? There are massive garbage patches floating around in the oceans, the vast majority of which are plastics. If you can get a big enough tanker and implement this system on it, you could probably cut the amount of fuel needed even further - the tanker goes into a garbage patch, melts all the plastic down, keeps the oil, and uses some of it to get back to land. It would probably be more effective than loading fleets of trucks.

You are vastly overestimating the density of these patches, probably due to media sensationalism. For example, the "Great Pacific Garbage Patch" [wikipedia.org] has a density of 4 particles per cubic meter of water. These particles are quite small, even microscopic. I know the news stories make it sound like it is just this mass of garbage floating around but that's just not how it is. From the Wikipedia article linked above:

"and the relatively low density of the plastic debris at, in one scientific study, 5.1 kilogram

Assuming that plastic is provided for free (cities or landfills are already pulling plastic out via a separation step) then enough energy can be *recovered* from the plastic to power the recovery process with a net gain. The goal is not energy independence... it's prevention of non-biodegradable items making it into the landfill.

There was a story a few months ago about an MIT project [inhabitat.com] to float a collector out into the ocean to pick up plastic... maybe these two teams should get together.

It's not the point. The point is to take a material that does nothing and to make it useful again. There's only so much plastic you can convert back into carpet and other non critical product. If this isn't BS and the result of the transformation is more fuel than what was used then it's a no brainer. The technology will be adopted and improved which will have even bigger ROI.

Currently we pay to get rid of plastic. This allows making plastic disposal lucrative and that in my books is a positive ROI.

I don't know how they define "cost effective", but since the plastic mostly came from oil in the first place, any energy expenditure to recover it is a net minus overall.

That would certainly be true when cost is compared to the original cost of the petroleum used to produce the plastic. Depending on the current price of oil, it may or may not be true now and in the future.

If your goal is to turn a waste product into oil, you need only be net efficient on the collection, conversion, and subsequent waste disposal. If it takes $0.80 of investment (collection, processing, distribution, waste cleanup) to produce a $1.00 worth of marketable product, then you've got a commercial venture. If it costs you up to $1.05 to do it, then you have a government contract possibility as you might be able to charge $0.20-$0.25 to

I don't know how they define "cost effective", but since the plastic mostly came from oil in the first place, any energy expenditure to recover it is a net minus overall.

While that is undoubtedly true it's likely that the energy is going to come from the waste plastic. Similarly coal fired power stations need to bleed off electricity to run crushers, conveyors, sootblowers etc.

but overall it is a fuel source with an energy return on investment (EROI) less than 1.

I'm all for eliminating waste, but if the net effect is that we're removing plastic from landfills and emitting it as CO2, that's not terribly different from digging up crude oil and emitting it as CO2.

Now, I'm sure there's some sort of multiplier here that makes it a bit better - perhaps the plastics are a cleaner source and less energy will be used to process it - but currently this carbon is sequestered in an inert if unattractive form whose dangers are mostly localized.

The goal isn't to burn this oil as tribute flames to our inventive manliness. It would replace an equivalent carbon portion of the fuel already burned, so there's no net increase in carbon, just that we would need to pull less out oil of the ground and put less plastic back in. (Okay, that's not quite what happens, oil just gets cheaper if you increase the supply so there is some net increase above the magical unicorn world where everything else stayed the same we would use less oil, but it's not as bad as

Depending on how much CO2 the machine creates, you may be coming up neutral or a bit ahead VS current oil extraction methods. After all, the machines that are used in oil-fields also use fuel and give off CO2.

Basically, you're lowering the need to extract raw/crude oil in favor of manufacturing it from plastic waste. It doesn't really affect your overall oil consumption/pollution - though it might affect pricing - but it does get rid of plastic waste buried in landfills. If they could similarly deal with st

I'm all for eliminating waste, but if the net effect is that we're removing plastic from landfills and emitting it as CO2, that's not terribly different from digging up crude oil and emitting it as CO2.

Now, I'm sure there's some sort of multiplier here that makes it a bit better - perhaps the plastics are a cleaner source and less energy will be used to process it - but currently this carbon is sequestered in an inert if unattractive form whose dangers are mostly localized.

It is terribly different in that unusable non-biodegradable material is removed, and as we develop new combustion systems and CO2 sequestration techniques, we know (should know) what to do with the CO2 exhaust.

There are no perfect solutions. Just alternatives, and it is up to us in being sufficiently smart (or at least in not being callously stupid) to string multiple alternatives into acceptable solutions.

Birds don't choke on CO2. Seriously while global warming is one problem non biodegradable pollution is another. For society digging up tar sands laying waste to nature is a third. You are potentially trading 2 environmental negatives for one, and depending on the use of energy that one negative could be sequestered.

While this converts waste plastic to oil it does not however:A.: complete this conversion at a less than or equal cost of energy generated by the oil. The shredder, crucible, and condenser arent powered by the mellow rock stylings of huey lewis and the news.B.: Absolve us from researching alternatives to crude oil, a fossil fuel that is finite in supply and directly contributing to climate change.

Our lust for oil has become all but indistinguishable from a heroin addicts search for a fix.

It said in the article that the plastic itself, once converted to fuel is used to fuel the process which is converting the plastic to fuel. In other words they pull off a little of the fuel converted from the plastic to fuel the process going forward. Other than the initial startup energy it should be energy independent.

Plastic is a nasty waste product (it doesn't biodegrade and it kills living things) that we need to find a way to either reuse or properly destroy. Converting the several trillion tons of plastic waste in US landfills into fuel oil not only saves the space in the landfills it recovers energy from a waste product. It's a good idea if the total economics of the setup are profitable enough to justify hauling it to a disposal site or small enough to build these at landfills. It's a damn good waste reduction technique that will ensure we don't end up with the planet in the movie Wall-E (which was buried in garbage like plastic waste).

It's interesting that you mention this. I actually have a relatively green process that I'm working on for extracting energy from waste, and it's primary source of input energy is "Hip to be Square". We do note high turnover in our lab assistants, however.

complete this conversion at a less than or equal cost of energy generated by the oil

How do you know this? Do you have access to information that shows it is not like the sewerage treatment that releases far more methane than is requited to power the treatment or are you just making a wild guess based on gut feeling and ignorance?

About 70 to 80 percent of the product comes out as oil. Roughly 10 to 20 percent becomes hydrocarbon gas that heats the system, while the remainder is char residue.

For every 10 units of plastic the system is fed, it generates 7-8 units of oil, 1-2 units of gas which powers the system, and 0-1 units of waste 'char residue'. So it produces quite a bit more fuel from the plastic than it consumes.

I didn't RTFA, but this is/. so that's a given. As I recall, plastic is the leftover waste from refining oil. That was one of the reasons it was so revolutionary to begin with. No one knew what to do with all of those tons of leftover sludge created by the refining process. If this process can convert plastic into some kind of useful fuel, I would think it would be more efficient to do so prior to creating the plastic to begin with.

Diesel is made from the sludge left over from refining oil... makes you wonder why it costs more than regular doesn't it?

It didn't used to cost more. My somewhat murky memory was that some portion of the population started to see the popularity of diesel vehicles during the Carter administration, especially since the fuel was so much cheaper. (We had a diesel rabbit... very bad idea for several reason, but I digress...) It seems that shortly after this mild shift in public consciousness, diesel prices started to spike.

Hell, you can (and we do) make any shorter-chain molecule by cracking.

Diesel oil is a bunch of mid-length chains and rings, which naturally exist in crude oil, and have been used that way for 110 years.

But since we want more gasoline & diesel oil than is naturally in crude, we crack the high-carbon molecules into the ones that we want more of (and then reform those too small into longer ones), instead of burning it in building boiler rooms, ships and making candles.

No it's just a heavier mix than petrol/gasoline, easier to make than petrol/gasoline but US refineries don't make a lot of it for some reason. The "sludge" ends up being used for things like making roads and/or gets cracked into lighter stuff.

It seems like one of the biggest issues with recycling plastics is all the different types, and each type having a different method to get back into a usable form. I see this as being really useful for breaking down big mixtures of plastic, where it would be too costly to sort them out. I wouldn't even use the oil for fuel, make more plastics!
Really, plastics has me more wrried about oil consumption in th elong-run, than the fuel usage itself.

The statement that there is 2 trillion tons of plastic in land fills got me wondering how much oil actually goes into producing something. From what I can gather a barrel of oil weighs about 300 pounds so if there aren't any other external inputs into making plastics that would mean that about 13 trillion barrels of oil have been turned into plastic. This doesn't seem the least bit right given that under 2 trillion barrels of oil have been extracted and not all of that went into making plastic. So how much oil actually goes into making plastic and how much is other stuff is use?

This leads me to my next question which is how much of the weight of the plastic is turned into oil? If it is over 1/6 of it then we have the equivalent of more than all presently extracted oil in our land fills already.

I figured that there were but I have no idea how much hence the question. Even with the number you provided it only makes things worse since the ratio of non to oil inputs for plastic would now be above 14:1 instead of my guessed 6:1 which seems even more doubtful. Also a billion tons of fairly dense rock makes a really fucking big hole in the ground [wikipedia.org] and plastic is much less dense than iron ore plus in land fills there would be lots of other stuff as well.

You start with one 10 ton/day reactor. Next quarter you build a 50 ton/day reactor. Then you build a 250 ton/day reactor. Then you build a 1000 ton per day reactor. Once you hit maximum scale that's economical, you reproduce the reactor and work on efficiency. Most petroleum refineries are not one big giant crude oil distillation unit. They're many systems working in parallel. And there's more than one refinery...

Pyrolysis for "recycling" plastic waste into oil (or tire waste into oil) has been around since at least the 1990s. The main problems are 2: A) As Irate Engineer states, a polymer is an "added value" and deconstructing polymers back to oil always fails economically when actual recycling to like-polymers is available, and B) as Itzy says, the comparative value of returning it to fuel, vs. leaving it in an Municipal Solid Waste to energy facility and burning it, is small.

I read TFA and cannot figure out what differentiates this from the pyrolysis "waste investments" of the 1990s, none of which really sailed.

let's start thinking of ways to reduce the amount of plastic we produce in the first place. I'm thinking mostly about all of the plastic packaging in our Big Box stores. we really do not need, have not needed in the past, to wrap a hammer in a plastic clam shell. It's not like it will go stale if we just hang it on a hook. If you must package non perishable items (to reduce shrink for instance) put it in a cardboard box. Using our finite petroleum resources to package non perishable items is crazy.

let's start thinking of ways to reduce the amount of plastic we produce in the first place. I'm thinking mostly about all of the plastic packaging in our Big Box stores. we really do not need, have not needed in the past, to wrap a hammer in a plastic clam shell.

You could drastically reduce the amount of plastic which hits the landfill by simply mandating that all bits of plastic used for packaging or in a product must be marked for recycling with a molded, stamped, melted, or otherwise permanent (not printed) mark. All those damned clamshells could be recycled if only they were marked. A handful of them are. It would be more efficient not to make them in the first place, but not marking them is just horribly irresponsible.

Your math is off. If there is demand for 100 barrels of oil for use as fuel, we will pull 100 barrels out of the ground and burn it. If we substitute 10 barrels of oil from recycled plastics, then we only pull 90 barrels of oil out of the ground. In both cases, we still burn the same 100 barrels of oil. The plastic existed already -- the energy required to pull the oil out of the ground and process the constituents into the chemicals pre-cursors for the plastic had already been spent. There's only a sm

oil is not getting cheaper, it's getting more expensive. The only reason the recycling of plastics and depolymerization of biomass is becoming "economical" is that the cost of crude pulled from the ground is exceeding the threshold for processing these other materials.

It's actually fairly cheap to manufacture "plastics" that can be used as raw materials by 3D printers from compostable materials that can be used to grow food if need be.

We only use plastics that are oil-based because we have lots of cheap material and the sludge from the separator columns on the refineries needs to be used for something. We could easily replace those with vegetable based rotation crops that have oils - in fact major US research universities have the basic patents to do just that (e.g. Univ

that never seems to quite come into production or actually get anywhere. I keep hoping, but.. sigh...

I'll still keep recycling my plastic (and hope they aren't kidding me and just dumping it into the landfill anyway). Even if it ends up being "recycled" into park benches or whatever, it's better than nothing.

That sounds a reasonable assertion, but wouldn't an enterprising landfill owner sitting on millions of pounds of plastic waste want to *additionally* make money converting some of the trash into something he could sell? Assuming it all penciled out, of course.